The present invention relates to communications access to digital computer networks. More specifically, it relates to how to automatically terminate a telephone uplink connection to a data network.
Cable modems use existing cable television connections to provide high-speed connections to access digital computer networks such as the Internet. A user establishing a connection to access the Internet using a cable modem will receive web pages from the Internet via a high-speed downstream connection from the cable television network headend system. A cable television network headend is a central location that is responsible for sending cable signals in a downstream direction. The cable television network headend also receives web pages from the Internet and forwards the web pages to the user""s cable modem over the high-speed downstream connection. This is a typical data-over-cable system.
Depending on the particular cable television system and cable modem implementation, a user typically sends commands and requests to the Internet in one of two ways: either (1) via an upstream connection directly back through the cable television network headend, or (2) over a separate telephone dial-up connection through the public switched telephone network (xe2x80x9cPSTNxe2x80x9d) to the cable television network headend. The latter case using a telephone dial-up connection through the PSTN is referred to as a data-over-cable system with telephony return.
A problem with using a data-over-cable system with a separate telephony return connection is coordinating the dropping of the telephone connection to the cable television network headend when the connection to the Internet is no longer being used. Although the user may no longer be using the connection, the cable modem may not be aware that the computer user has turned off the computer and is no longer using the telephone dial-up connection. The cable modem device itself also will not immediately drop the telephone line connection even when the user turns his or her computer off. The telephone dial-up connection to the cable television system is maintained with no activity from the user, all the while accumulating telephone charges and monopolizing the use of telephone line.
Typically, in a data-over-cable system with telephony return, the cable television network headend device sends an information message to the cable modem so that the cable modem can to initiate a telephone call, as directed by a computer attached to the cable modem, for example. The message contains an inactivity timeout value for a timer located on the cable modem. The cable modem regularly monitors its interface to the telephone line connection for outgoing data transmission activity. If the timer is activated, and if there is no outgoing activity monitored at the interface for the length of the inactivity timeout period, the cable modem will drop the telephone line connection. If outgoing activity is monitored, the inactivity timer is reset.
Two issues that arise are (1) the length of time set for the inactivity timeout and (2) the notion that any outgoing data activity on the telephone line will cause the inactivity timer to reset. The value for the inactivity timeout period as set by the cable television network headend may be of a significant duration, making it impossible for the cable modem to readily discern that a particular customer computer or consumer premise equipment has stopped transmitting and is no longer using its telephone line connection. Apart from the length of time for the timeout, the inactivity timer cannot narrowly focus on discerning that consumer premise equipment is no longer on-line or active. This is because the inactivity timer is reset by any outgoing activity at the telephone line interface. The cable modem, for example, may regularly update its network address more often than the length of the inactivity timer, so that, in theory, the telephone line connection will never be dropped due to inactivity.
In accordance with preferred embodiments of the present invention, some of the problems associated with using a telephone dial-up or uplink connection to a data network, such as with a cable modem using a telephone return line, are addressed.
The present invention includes a method of automatically terminating a telephone dial-up connection to a data network. A network device which utilizes the telephone dial-up connection to access the data network is provided. The network device has a network interface to one or more consumer premise equipment, or CPE. In accordance with the exemplary method, the network interface is monitored for incoming data transmission activity and an absence of incoming activity is determined. The one or more CPE are queried for their status, and any responses to the query from the one or more CPE are received. If no response is received from at least one of the one or more CPE, the telephone dial-up connection is terminated.
A further embodiment of the present invention includes a system for automatically terminating a telephone dial-up connection to a data network, having a network device, a network interface, one or more CPE, a querying process, and preferably a termination process. The network device utilizes the telephone dial-up connection to transmit data to the data network. The one or more CPE utilize the network device via the network interface to transmit data over the telephone dial-up connection. The querying process queries the status of the one or more CPE and, preferably, determines whether the network device is no longer being utilized by the one or more CPE to transmit data over the telephone dial-up connection. Preferably, the termination process terminates the telephone dial-up connection if the network device is no longer being utilized by the one or more CPE.
A preferred embodiment of the present invention attempts to address some of the problems in automatically and locally terminating a telephone dial-up connection in a data-over-cable system with telephony return. A cable modem is connected on an upstream telephone dial-up connection to a data network such as the Internet. The cable modem monitors a network interface for incoming data transmission activity from consumer premise equipment, including a personal computer system, connected to the cable modem. If the cable modem determines no incoming data transmission activity, the cable modem begins to query the status of the consumer premise equipment. If the consumer premise equipment does not respond to repeated queries within a specified time, the cable modem terminates the telephone dial-up connection.
Presented is a cable modem device that automatically drops a telephone line connection more quickly than as directed by the inactivity timeout set by the cable television network headend. A user who turns his or her computer off or no longer wishes to connect to the Internet will be able to use his or her telephone line for other purposes more immediately and will be more likely to decrease his or her telephone usage charges than under the present cable modem termination system.
The foregoing and other features and advantages of a preferred embodiment of the present invention will be more readily apparent from the following detailed description, which proceeds with references to the accompanying drawings.